Fueling system

ABSTRACT

An apparatus for providing fuel comprises a fuel handling portion and an air handling portion. The fuel handling portion comprises a fuel tank adapted to store fuel as well as a fuel nozzle in fluid communication with the fuel tank and adapted to dispense fuel from the fuel tank. The air handling portion comprises an air tank adapted to be filled with pressurized gas from a pressurized gas source. After the pressurized gas source is removed, the air handling portion is operative to apply the pressurized gas from the air tank to the fuel in the fuel tank so as to provide a motive force for dispensing fuel through the fuel nozzle.

FIELD OF THE INVENTION

The present invention relates to apparatus and methods for obtaining, transporting, storing, and dispensing fuel. The present invention further relates to apparatus and methods for processing fuel.

BACKGROUND OF THE INVENTION

Operators of motorized equipment such as auto enthusiasts, pilots, boaters, landscapers, and the like often find themselves requiring gasoline without having a convenient source of suitable fuel. To make matters worse, in many cases, a ready source of electrical power is also not available. During these situations, the only realistic fueling solution is frequently the ubiquitous five-gallon gas can. The user fills several of these gas cans at a remote gas station and then transports them to where they will be needed. The user then lifts the heavy gas cans above the vehicle's fuel tank and uses a spout or funnel to direct the fuel into the vehicle by gravity feed. In the case of large vehicles and high-wing airplanes, the user may even need to climb a stepstool or ladder with the cans in order to access the vehicle's fuel tank.

To make matters worse, in addition to being inconvenient and physically demanding, the use of gas cans in this manner is often dangerous from the perspective of explosion and fire, and also frequently results in fuel spillages that can damage a vehicle's paint. A user may even lose their grip on the gas can while fueling and allow the gas can to inadvertently drop onto the vehicle and cause damage. Finally, fueling with gas cans is slow because of a gas can's narrow opening and its dependence on gravity feed. Taking an inordinate amount of time to fuel a vehicle is especially inconvenient when the weather is cold or wet and the refueling is performed while the operator is exposed to the elements.

A further source of issues for the equipment operators mentioned above is the inclusion of alcohol in many fuels. Almost all regularly available automobile gasoline now contains 10% ethanol as a result of federal legislation. Nevertheless, ethanol can destroy critical fuel system and engine components if these components were not specifically designed for resistance to alcohol. Ethanol also has a tendency to phase separate from gasoline when exposed to water, creating a corrosive layer of water and ethanol at the bottom of a fuel tank. For these reasons, alcohol-containing fuels are not approved for many motorized vehicles. A large percentage of the piston-engine aircraft fleet, for example, is certified to run on automobile fuel so long as it is free of alcohol. Despite this, however, a pilot typically must use very expensive and highly polluting leaded aviation fuel instead of automobile fuel because the automobile fuel contains ethanol.

For the foregoing reasons, there is a need for improved fueling system designs that allow fuel to be obtained, transported, stored, and dispensed in a safe, efficient, and convenient manner. For those vehicles that cannot tolerate alcohol in the fuel, there is further a need for these new fueling systems to be capable of removing any ethanol from the fuel before the fuel is dispensed into the vehicle.

SUMMARY OF THE INVENTION

Embodiments of the present invention address the above-identified needs by providing fueling systems that allow fuel to be obtained, transported, stored, and dispensed in a safe, efficient, and convenient manner. Embodiments of the invention further provide fueling systems capable of removing any ethanol from the fuel before the fuel is dispensed into a vehicle.

In accordance with an aspect of the invention, an apparatus for providing fuel comprises a fuel handling portion and an air handling portion. The fuel handling portion comprises a fuel tank adapted to store fuel as well as a fuel nozzle in fluid communication with the fuel tank and adapted to dispense fuel from the fuel tank. The air handling portion comprises an air tank adapted to be filled with pressurized gas from a pressurized gas source. After the pressurized gas source is removed, the air handling portion is operative to apply the pressurized gas from the air tank to the fuel in the fuel tank so as to provide a motive force for dispensing fuel through the fuel nozzle.

In accordance with another aspect of the invention, a method of providing fuel comprises filling a fuel tank with fuel, the fuel tank in fluid communication with a fuel nozzle. Subsequently an air tank is pressurized with a gas from a pressurized gas source. With the pressurized gas source removed, fuel is dispensed from the fuel tank through the fuel nozzle while allowing pressurized gas from the air tank to provide a motive force for dispensing the fuel.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description and accompanying drawings where:

FIG. 1 shows a schematic of at least a portion of a fueling system in accordance with a first illustrative embodiment of the invention;

FIG. 2 shows a flow diagram of an illustrative method for utilizing the FIG. 1 fueling system to dispense fuel;

FIG. 3 shows a perspective view of a working prototype of the FIG. 1 fueling system implemented in a cart;

FIG. 4 shows a schematic of at least a portion of a fueling system in accordance with a second illustrative embodiment of the invention;

FIG. 5 shows a flow diagram of a method for utilizing the FIG. 4 fueling system to remove alcohol and dispense fuel;

FIGS. 6A and 6B show flow diagrams of an automated separation process in the FIG. 4 fueling system;

FIG. 7 shows an electrical schematic of an illustrative detector in the FIG. 4 fueling system;

FIG. 8 shows a flow diagram of alternative steps for use in the FIGS. 6A and 6B process; and

FIG. 9 shows a perspective view of a working prototype of the FIG. 4 fueling system implemented in a cart.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be described with reference to illustrative embodiments. For this reason, numerous modifications can be made to these embodiments and the results will still come within the scope of the invention. No limitations with respect to the specific embodiments described herein are intended or should be inferred.

FIG. 1 shows a schematic of at least a portion of a fueling system 100 in accordance with a first illustrative embodiment of the invention. The fueling system 100 can be roughly broken into two portions. An air handling portion 105 allows the storage and transport of compressed air, and also provides a means for a fuel tank 110 to be pressurized with air. A fuel handling portion 115 allows the storage and transport of fuel, and also provides a means for the fuel to be dispensed.

Broken down even further, the air handling portion 105 comprises an air path 120 between an air tank 125 and the fuel tank 110. Along a section of the air path 120 immediately after the air tank 125, one finds an air tank pressure gauge 130, an air tank safety relief valve 135, an air tank fill valve 140, an air tank valve 145, and a pressure regulator 150. Immediately after the pressure regulator 150, one finds a fuel tank relief valve 155, an air filter 160, an air shutoff valve 165, a fuel tank safety relief valve 170, and a fuel tank pressure gauge 175. In the fuel handling portion 115 of the fueling system 100, one finds the fuel tank 110 with a fuel cap 112, as well as a fuel path 180 that connects the bottom of the fuel tank 110 to a fuel shutoff valve 185, a fuel filter 190, and finally, a fuel nozzle 195. The fuel path 180 from the fuel filter 190 to the fuel nozzle 195 comprises a fuel hose 182.

For safety purposes, the fueling system 100 further comprises an electrical grounding system that allows all the components of the fueling system 100 to be electrically tied to the vehicle being fueled. This equalizes the electrical potential between the fueling system 100 and the vehicle, thereby reducing the chance of a spark forming during fueling. A bonding strap 198 is attached to the fuel tank 110 and is available to tie the fueling system 100 to the vehicle being fueled. The electrically conductive conduits and fixtures forming the fueling system 100, in addition to a grounding wire integral to the fuel hose 182, assure that all the parts of the fueling system 100 achieve the same electrical potential as the bonding strap 198.

When the air handling portion 105, the fuel handling portion 115, and the grounding system are combined, one achieves a fueling system 100 that allows fuel to be obtained, transported, stored, and dispensed in a safe, efficient, and convenient manner. Pressurization provided by the air handling portion 105 allows the fuel tank 110 to be pressurized with air. Fuel flow from the fuel tank 110, in turn, is driven by this air pressure (i.e., air pressure creates the motive force for the fuel flow) and does not depend solely on gravity. Ultimately, a user of the fueling system 100 receives a fueling experience similar to that of a conventional gas pump, but without the need for an immediate source of electrical power.

FIG. 2 shows a flow diagram of an illustrative method 200 for utilizing the fueling system 100 to dispense fuel. The first set of steps allows the fuel tank 110 to be pressurized with air from the air tank 125. In step 205, the fuel tank 110 is vented of any excess pressure by closing the air tank valve 145, and then opening the air shutoff valve 165 and the fuel tank relief valve 155. Once this venting is accomplished, the user then shuts the air shutoff valve 165 and the fuel tank relief valve 155 and moves onto step 210, wherein the fuel tank 110 is filled with fuel. Here, the user merely removes the fuel cap 112 of the fuel tank 110 and dispenses fuel into the fuel tank 110 from a convenient source of fuel (e.g., an automobile gas station). After the fuel cap 112 is replaced, the air tank 125 is then filled with compressed air in step 215. Filling the air tank 125 may be performed by coupling a source of compressed air (i.e., an air compressor) to the air tank fill valve 140 and filling the air tank 125 while the air tank valve 145 remains closed.

The fuel tank 110 is then ready to be pressurized. In step 220, the fueling system 100 is grounded to the vehicle being fueled. In step 225, the air tank valve 145 and the air shutoff valve 165 are opened causing compressed air to travel from the air tank 125 through the pressure regulator 150 and the air filter 160 into the fuel tank 110. The pressure regulator 150 reduces the air pressure from the fill pressure in the air tank 125 (e.g., 120 pounds per square inch (psi)) to something substantially lower than that (e.g., 10 psi). The air filter 160, in turn, removes any contaminants from the compressed air before the contaminants have a chance to enter the fuel tank 110. Pressurized in this manner, the fuel tank 110 is ready to dispense fuel. In step 230, the user opens the fuel shutoff valve 185 and positions the fuel nozzle 195 in a vehicle's fuel tank opening. Actuating the fuel nozzle 195 causes fuel to first travel through the fuel filter 190 and then into the vehicle.

Notably, during the entire method 200 described above, any potentially dangerous over-pressure events are avoided by the air tank safety relief valve 135 and the fuel tank safety relief valve 170. The air tank safety relief valve 135 may be configured to vent when the pressure in the air tank 125 exceeds, for example, 145 psi. The fuel tank safety relief valve 170 may be configured to vent when the fuel tank 110 exceeds, as another example, 25 psi.

The fueling system 100 may be physically implemented in several different forms. FIG. 3, for example, shows a perspective view of a working prototype of the fueling system 100 implemented in a cart 300 with two rear wheels 305, a front base 310, and two handles 315. A region 320 of the working prototype comprised the air tank pressure gauge 130, the air tank safety relief valve 135, and the air tank fill valve 140; while another region 325 comprised the air tank valve 145, the pressure regulator 150, the fuel tank relief valve 155, the air filter 160, the air shutoff valve 165, the fuel tank safety relief valve 170, and the fuel tank pressure gauge 175. A region 330 near the bottom of the cart 300 comprised the fuel shutoff valve 185 and the fuel filter 190. This prototype and others displayed excellent reliability and robustness. Fuel flow rates were often greater than those provided by gas pumps at automobile gas stations. For example, flow rates greater than eight gallons per minute were achieved with a ⅜-inch diameter fuel hose 182 even with a partially used fuel filter 190.

Advantageously, the fueling system 100 can be constructed using conventional, off-the-shelf components, reducing the need to manufacture custom parts. In one configuration, for example, the air tank 125 and the fuel tank 110 may comprise conventional air-tight metallic tanks. Both tanks are preferably rated to about five times the normal maximum operating pressure to provide a wide margin of safety. The air tank valve 145, the fuel tank relief valve 155, the air shutoff valve 165, and the fuel shutoff valve 185 may comprise conventional ball valves, while the air tank fill valve 140 may comprise a conventional Schrader valve. The air tank safety relief valve 135 and the fuel tank safety relief valve 170 may comprise conventional adjustable pressure relief valves. The pressure gauges 130, 175, the pressure regulator 150, the air filter 160, the fuel filter 190, and the fuel nozzle 195 may just be conventional components readily sourced from a number of commercial vendors. Lastly, the air path 120 and the fuel path 180 that tie the various other components together may comprise conventional metallic fittings, metallic tubing, conventional rubber hoses, and a conventional grounded fuel hose 182.

As described earlier, the inclusion of ethanol in a lot of fuels provides a barrier to the use of that fuel in many vehicles. FIG. 4 shows a schematic of at least a portion of fueling system 400 in accordance with a second illustrative embodiment of the invention that addresses that issue. The fueling system 400 includes an air handling portion 105 identical to the air handling portion 105 in the fueling system 100 (and therefore marked with the identical reference numeral). The fuel handling portion 410, on the other hand, comprises a number of added elements that allow ethanol to be removed from the fuel using an automated separation process. The fuel handling portion 410 comprises a fuel tank 415 with a fuel cap 417, and a bonding strap 418. The fuel tank 415 has an output at its bottom that is split into two branches. On a first branch, the fuel flow is directed through a first fuel shutoff valve 420 into a first fuel filter 425 and ultimately to a fuel nozzle 430 via a fuel hose 432. On a second branch, the fuel is directed to a second fuel shutoff valve 435, to a second fuel filter 440, and to a motorized source selector valve 445. The source selector valve 445 is connected to a water source 450. After the motorized source selector valve 445, the fuel (or the water or ethanol-water, as the case may be) is directed to a detector 455, to a pump 460, and finally to a motorized waste selector valve 465. The waste selector valve 465 determines whether the fluid in the fuel tank 415 is pumped to a waste container 470 or back to the top of the fuel tank 415.

FIG. 5 goes on to show a flow diagram of a method 500 for utilizing the fueling system 400 to remove alcohol from fuel and ultimately dispense the alcohol-free fuel into a vehicle. In step 505, the fuel tank 415 is vented in a manner similar to step 205 in the method 200. Next, in step 510, ethanol-containing fuel is added to the fuel tank 415 in a manner similar to step 210. In the next step, however, the method 500 diverges from that described earlier. In step 515, a quantity of water (e.g., about one gallon) is also added to the fuel tank 415. Moreover, in step 520, additional water is added to the water source 450. In step 525, the automated separation process 600 is initiated.

The automated separation process 600 in the fueling system 400 is controlled by a controller 475. The controller 475 receives signals from the detector 455 and controls the states of the source selector valve 445, the pump 460, and the waste selector valve 465. The automated separation process 600 leverages the fact that ethanol in fuel phase separates from that fuel when exposed to water, thereby forming an ethanol-water layer that is heavier than the remaining fuel and settles below that fuel. Causing the phase separation to occur and then removing the bottom layer of ethanol-water thereby becomes a means of removing the alcohol from the fuel.

FIGS. 6A and 6B show flow diagrams of the illustrative automated separation process 600 in the fueling system 400. In step 602, the controller 475 sets a variable FILLS to zero (i.e., FILLS=0). It then commands the source selector valve 445 to route fuel from the second fuel filter 440 to the detector 455 (step 604), and also commands the waste selector valve 465 to route fluids from the pump 460 back to the top of the fuel tank 415 (step 606). Subsequently, in step 608, the controller 475 commands the pump 460 to turn on and run for a time PUMPTIME1 (e.g., 10 minutes). This starts to circulate the fuel-ethanol-water from the bottom of the fuel tank 415 to its top, thereby thoroughly mixing the fuel-ethanol-water and starting the process of phase separation. After the pump 460 is stopped, the controller 475 in step 610 commands the waste selector valve 465 to start sending fluid to the waste container 470 instead of back to the top of the fuel tank 415.

In steps 612 and 614, the controller 475 attempts to remove any ethanol-water that has collected at the bottom of the fuel tank 415. This involves the use of the detector 455. FIG. 7 shows an exemplary electrical schematic of the detector 455. In the present embodiment, the detector 455 comprises two brass plugs 705 that are spaced apart and between which the fluids from the fuel tank 415 are allowed to flow. Ethanol-water creates a high conductivity between the brass plugs 705, while fuel creates a low conductivity. The conductivity is detected through the use of a DC voltage source, a pull-up resistor 710, and a series resistor 715, as shown in the schematic. A high conductivity between the brass plugs 705 causes the voltage sent to the controller 475 to be low, and vice versa.

Again referring to FIGS. 6A and 6B, in step 612, the pump 460 is turned back on, sending the fluid from the bottom of the fuel tank 415 to the waste container 470. In step 614, the controller 475 receives the conductivity, CNDCT, from the detector 455 and determines whether CNDCT is higher than a predetermined conductivity threshold, CTHRESH. If CNDCT>CTHRESH, meaning that the detector 455 is seeing ethanol-water, the pump 460 is allowed to keep on pumping. When CNDCT<CTHRESH, meaning that the detector 455 is seeing primarily ethanol-free fuel, the controller 475 turns off the pump 460 in step 616.

In the present embodiment, additional water is incrementally added to the fuel in the fuel tank 110 and allowed to circulate for PUMPTIME1 in a series of “water fills” in order to assure that the substantial majority of ethanol has been successfully removed. The additional water fills also aid in diluting the ethanol-water mixture in the waste container 470, making its ultimate disposal less hazardous and easier from a regulatory standpoint. In step 618, the controller 475 determines whether the fuel in the fuel tank 415 has been exposed to a predetermined number of water fills, MINFILLS. If not, the waste selector valve 465 in step 620 is set such that it again routes fluids to the top of the fuel tank 415 rather than to the waste container 470. Subsequently, in step 622, the controller 475 commands the source selector valve 445 such that it receives water from the water source 450 rather than from the second fuel filter 440. The pump 460 is then allowed to run for a time PUMPTIME2 in step 624. The time PUMPTIME2 is preferably set so that about one gallon of water is caused to be pumped from the water source 450 into the fuel tank 415, although other water quantities may be chosen if desired. With the additional water added in this manner, the variable FILLS is incremented by one in step 626. Steps 604-626 are repeated until the number of additional water fills is equal to MINFILLS. At that point, the process 600 progresses to step 628 in FIG. 6B.

The remaining steps in the automated separation process 600 give any additional ethanol-water in the fuel tank 415 additional time to settle out without the fluid in the fuel tank 415 being circulated by the pump 460. This additional time is called “dwell time.” Dwell time is measured by having a counter, CNTR, in the controller 475 advance until it reaches a predetermined counter value, CNTRDWELL. In step 628, CNTR is set to zero. In step 630, the detector 455 determines whether CNDCT exceeds another predetermined conductivity value, CHIGH. CHIGH is a conductivity value greater than CTHRESH, and is used during the dwell time to avoid having the user wait through the entire dwell time when there is still a lot of ethanol-water collecting at the bottom of the fuel tank 415. If CNDCT>CHIGH in step 630, the controller 475 turns the pump 460 back on (step 632) and runs the pump 460 for a time PUMPTIME3 (e.g., two seconds), thereby using the pump 460 to send more fluid to the waste container 470. The pump 460 then turns back off, reinitiating the dwell time by reverting back to step 628. If CNDCT<CHIGH in step 630, the CNTR is advanced by one in step 634 and the controller 475 proceeds to step 636.

Step 636 determines whether CNTR>CNTRDWELL has been achieved, meaning that the fueling system 400 has waited the predetermined dwell time in order to allow complete phase separation. If no, the controller 475 proceeds back to step 630. If yes, the controller 475 moves to step 638, where it again checks if CNDCT>CTHRESH. This is the final measurement to determine if all the ethanol-water has been removed from the fuel tank 415. If the result is no, the controller 475 assumes that all the ethanol-fuel has been removed. If the answer is yes, the controller 475 assumes that ethanol-water still remains, and moves back to step 632. The pump 460 is again run for PUMPTIME3 and the dwell time starts again in step 628.

With the alcohol now removed from the fuel, the fuel can be dispensed in a manner similar to the fueling system 100. Again referring to FIG. 5, step 530 has the user fill the air tank 125 with compressed air in a manner similar to step 215. In step 535, the fueling system 400 is properly grounded to the vehicle. Lastly, in steps 540 and 545, the fuel tank 110 is pressurized and the fuel is dispensed as was done in steps 225 and 230, respectively.

The illustrative automated separation sequence can be modified and the results would still come within the scope of the invention. One such modification involves replacing step 608 in the automated separation process 600 shown in FIGS. 6A and 6B with the sequence of steps 802-806 shown in FIG. 8. Step 608 in the process 600 causes the fuel-ethanol-water to be circulated through the fuel tank 110 for the time PUMPTIME1. Steps 802-806 in FIG. 8, in contrast, use the detector 455 to determine the circulation time. More particularly, in step 806, CNDCT is measured to see if it is below a predetermined conductivity, CCIRC. If yes, it is assumed that most, if not all, of the ethanol-water has phase separated from the fuel and is at the bottom of the fuel tank 415. The circulation process may then be stopped. If no, it is assumed that more circulation is required and that process is allowed to continue.

Like the fueling system 100, the fueling system 400 may also be manufactured using conventional, commercially available components. The fuel tank 415, the first fuel shutoff valve 420, the fuel hose 432, and the fuel nozzle 430 may comprise the same components as their respective counterparts in the fueling system 100. That said, it is preferred that the first fuel filter 425 be of the “water-block” variety to create a final barrier to dispensing any water into a vehicle. Suitable water-block fuel filters are conventional and are commercially available. Likewise, the second fuel shutoff valve 435 may comprise a conventional ball valve, while the second fuel filter 440 may comprise a conventional fuel filter (non water-block type). The pump 460 may be a conventional electric fuel pump and the selector valves 445, 465 may be conventional electric fuel tank selector valves.

For logic functions, the controller 475 may include any suitable, commercially available microcontroller chip such as, but not limited to, a PIC-type microcontroller. Once its functions are understood, one of ordinary skill in the electronics arts would recognize how to program the microcontroller and how to configure any additional circuitry in the controller 475 needed to interface the microcontroller with the pump 460, the detector 455, and the selector valves 445, 465. Moreover, programming and interfacing microcontrollers are described in a number of books, including Valdes-Perez et al., Controllers: Fundamentals and Applications with PIC, CRC Press, 2009, which is hereby incorporated by reference herein. Power may be supplied to the controller 475 by battery (standard or rechargeable) or by line power. Displays may be added to the controller to indicate the various phases of the separation process such as draining, settling, and separating. Alarms and other features may also be programmed into the controller 475 to indicate fouled filters, inoperative pumps, out-of-range detector measurements, electrical faults, and the like.

FIG. 9 shows a perspective view of a working prototype of the fueling system 400 implemented in a cart 900 with two rear wheels 905, a front base 910, and two handles 915. A region 920 of the working prototype comprised the air tank pressure gauge 130, the air tank safety relief valve 135, and the air tank fill valve 140; while another region 925 comprised the air tank valve 145, the pressure regulator 150, the fuel tank relief valve 155, the air filter 160, the air shutoff valve 165, the fuel tank safety relief valve 170, the fuel tank pressure gauge 175, the first fuel shutoff valve 420, and the first fuel filter 425. A region 930 near the bottom of the cart 900 comprised the second fuel shutoff valve 435, the second fuel filter 440, the motorized source selector valve 445, the detector 455, the pump 460, the motorized waste selector valve 465, and the controller 475. Additional hoses were provided for connection to the water source 450 and the waste container 470 (not shown). In this prototype, it will be noted that the first fuel filter 425 (e.g., water-block type) was elevated on the cart 900 so that it was higher than the fuel tank 415. Such a configuration is preferable; it helps to ensure that the first fuel filter 425 is not flooded with ethanol-water from the fuel tank 415, and that the first fuel filter 425 provides the greatest effectiveness in removing any residual water from the fuel while the fuel is ultimately being dispensed.

It should again be emphasized that the above-described embodiments of the invention are intended to be illustrative only. Other embodiments can use different types and arrangements of elements, as well as different process steps, for implementing the described functionality and the results will still come within the scope of the invention. For example, in another embodiment, the air tank may not be present or the air tank may be removable, and the fueling system may be configured to receive compressed air from an external source such as an external compressed air tank or an air compressor. In another example, a detector might use capacitive, inductive, or optical measurements instead of a conductivity measurement to determine the presence and absence of ethanol-water. Alternatively or additionally, another embodiment may even comprise several air tanks and/or several fuel tanks to increase the capacity of the fueling system as well as to provide for even faster fuel flow rates. These numerous alternative embodiments within the scope of the invention will be apparent to one skilled in the art.

Moreover, all the features disclosed herein may be replaced by alternative features serving the same, equivalent, or similar purposes, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features. 

1. An apparatus for providing fuel, the apparatus comprising: a fuel handling portion, the fuel handling portion comprising a fuel tank adapted to store fuel, and a fuel nozzle in fluid communication with the fuel tank and adapted to dispense fuel from the fuel tank; and an air handling portion, the air handling portion comprising an air tank adapted to be filled with pressurized gas from a pressurized gas source and the air handling portion operative to, after the pressurized gas source is removed, apply the pressurized gas from the air tank to the fuel in the fuel tank so as to provide a motive force for dispensing fuel through the fuel nozzle.
 2. The apparatus of claim 1, wherein the fuel handling portion comprises a fuel filter.
 3. The apparatus of claim 1, wherein the air handling portion comprises a pressure regulator operative to modify a pressure of the pressurized gas from the air tank before it is applied to the fuel in the fuel tank.
 4. The apparatus of claim 1, wherein the air handling portion comprises an air filter operative to filter the pressurized gas from the air tank before it is applied to the fuel in the fuel tank.
 5. The apparatus of claim 1, further comprising an electronic controller.
 6. The apparatus of claim 5, wherein the electronic controller is in signal communication with a detector that allows the electronic controller to determine a composition of fluid received from the fuel tank.
 7. The apparatus of claim 6, wherein the determination is based at least in part on an electrical conductivity of the fluid.
 8. The apparatus of claim 5, wherein the electronic controller is operative to control one or more pumps.
 9. The apparatus of claim 5, wherein the electronic controller is operative to control one or more motorized selector valves.
 10. The apparatus of claim 5, wherein the electronic controller is operative to cause fluids from the fuel tank to be returned back to the fuel tank.
 11. The apparatus of claim 5, wherein the electronic controller is operative to cause fluids from the fuel tank to be delivered to a waste container.
 12. The apparatus of claim 5, wherein the electronic controller is operative to cause water from a water source to be introduced into the fuel tank.
 13. The apparatus of claim 1, wherein the apparatus is at least partially implemented in the form of a rolling cart.
 14. A method of providing fuel, the method comprising the steps of: filling a fuel tank with fuel, the fuel tank in fluid communication with a fuel nozzle; pressurizing an air tank with a gas from a pressurized gas source; removing the pressurized gas source; and dispensing the fuel from the fuel tank through the fuel nozzle while allowing pressurized gas from the air tank to provide a motive force for dispensing the fuel.
 15. The method of claim 14, further comprising the step of introducing water into the fuel.
 16. The method of claim 14, further comprising the steps of introducing water into the fuel tank a plurality of separate times.
 17. The method of claim 14, further comprising the step of mixing the contents of the fuel tank.
 18. The method of claim 14, further comprising the step of waiting a predetermined time for the contents of the fuel tank to settle without mixing the fluid in the fuel tank.
 19. The method of claim 14, further comprising the step of determining a composition of fluid received from the fuel tank.
 20. The method of claim 14, further comprising the step of pumping fluid from the bottom of the fuel tank and sending the fluid to a waste container. 